SD Drop Causes

[adrian_122003]

Hi everyone,

i would just like to ask what can be the main causes of High SD Drops we encountered in some sites.
i have checked the Hardware via MML and no alarms were found, but the quality of TRXs are low.
can this still be caused by the hardware?
there are also no interference.
our vendor is NSN.
your feedback will be greatly appreciated.
thank you.

[maha18love]

HI

increase the T200 SDCCH timer, it might help

[lamagica]

hi adrian, you can check the main contributor for the SDCCH Drop, is it becuase of rf, abis, or aif problem..
Is your equipment FMR or common abis (siemens bts plus connected to flexi bsc), you should also try to reset the bcf, sometimes it works..

[idea5000]

For E///

High sdcch drop due to other reasons could be lead by :
1. Transmission Flicker
2. Power issue
3. Hardware issue ( DRU, TX or RX ) Trial Lock and Unlock absolutely working and hourly monitoring.
4. Sleeping DRU suspected ( Increased SDCCH Drop > 15 %, Tch Assignment succes rate < 90 % and Ho Incoming succes rate < 95 %.

[plannerguy]

Hi

Try remapping SD to better TRX


Regards'
Plannerguy

[Fado]

Hi everyone,

i would just like to ask what can be the main causes of High SD Drops we encountered in some sites.
i have checked the Hardware via MML and no alarms were found, but the quality of TRXs are low.
can this still be caused by the hardware?
there are also no interference.
our vendor is NSN.
your feedback will be greatly appreciated.
thank you.

hi,did you check IOI?it may show you if there is an hardware issue with TRXs...

[ashraferto]

HI ,
Check the below counters for deep investigation:

SDCCH_RF_OLD_HO
SDCCH_LAPD_FAIL
SDCCH_BTS_FAIL
SDCCH_USER_ACT
SDCCH_BCSU_RESET
SDCCH_NETW_ACT

[peanut]

hi adrian, you can check the main contributor for the SDCCH Drop, is it becuase of rf, abis, or aif problem..
Is your equipment FMR or common abis (siemens bts plus connected to flexi bsc), you should also try to reset the bcf, sometimes it works..

You're right you need to split the drops to reasons and see the main contributor reason

Regards,

[ashraferto]

hi adrian, you can check the main contributor for the SDCCH Drop, is it becuase of rf, abis, or aif problem..
Is your equipment FMR or common abis (siemens bts plus connected to flexi bsc), you should also try to reset the bcf, sometimes it works..

yes a agree with you..in GEMINI this problem sometimes solved by reset BCF

[aaofik]

do you check TQM and ND196? if there low qual trx in ND196 lower than 90% and there is not alarm, it because not yet trigger alarm. try to ask TI to check installation modul as jumper etc, and if appear try to replace rf modul. it happen in my site.